If the confederate flag is supposedly all about southern pride heritage, then why do hate groups use the flag and why hasn't the people who claim the?

The flag isn't racist called out racists for using the flag? klan, skinheads and other hate groups use the flag. Why hasn't supporters say anything about that instead of telling blacks and other minorities that the flag isn't racist? I have yet to hear ONE supporter speak out. Why haven't all of these people who claim its not racist got together and sue the klan, neo nazis and other hate groups for defamation of character?

You can't just appropriate someone else's work and trademark it. That's intellectual property theft. It doesn't matter if they're now dead. It needed to be done when the flag was created, by the creator or their assigned agent (s). It cannot be done now. It'd be as if you tried to trademark the US flag or any state flag now. The USPTO would throw your claim out because you don't have exclusive rights to the design. I am just addressing your legal question. Someone who is a supporter of the CBF will have to address your other question.